Relay



D. C. DAVIS AND C. LE G. FORTESCUE.

RELAY.

APPLlcAnoN man Junin, 1918. 1,351,027. Patented Aug. 31, 1920.

L L/ 5 Q Wi? F4 UNITED STATES PATENT OFFICE.

DAVID C. DAVIS, OF WILKINSBURG, AND CHARLES LE G. FORTESCUE, 0F PITTSBURGH,

PENNSYLVANIA, ASSIGNOBS TO WESTINGHOUSE ELECTRIC AND MANUFACTUR- ING COMPANY, A CORPCBATION 0F PENNSYLVANIA.

RELAY.

Application led June 17,

To all whom t may Concern:

Be it known that we, DAviD DAVIS, a citizen of the United States, and a resident of Wilkinsburg, in the county of Allegheny and State of Pennsylvania, and CHARLES LE G. Fon'rnsoma, a subject of the King of Great Britain, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Relays, of which the following is a specification.

Our invention relates to relays and particularly to electrical relays that are variably responsive to the frequency of the actuating current.

One object of our invention is to provide a relay` the armature of which shall be actuated in a direction in accordance with the frequency of the actuating curient.

Another object of our invention is to provide-a relay of the above-indicated character that shall be inexpensive to construct and e'ective in its operation.

In practising our invention, we provide an actuating electromagnet, an armature therefor, a windin for the armature that is inductively relate to the actuating winding of the electromagnet, and reactors and con densers so connected in closed-circuit relation to the winding of the armature that f impedance of the circuit of the armature .winding be so controlled that, under predetermined conditions, it will permit the armature to be attracted b the actuating elcctroma et and, under otervpredetermined con ditions of frequency, will prevent the armature from being actuated or permit'it to be actuated in another direction.

In the accompanying drawings, Figure 1 is a diagrammatic view of a relay embodying our invention; and Figs. 2, 3 and 4 are diagrammatic views. of relays embodying modified forms of our invention.

The relay 1 comprises, in general, an actuating electromagnet 2, a ivotally mounted. armature 3, and means 4 or controlling the operation of the armature.

The electromagnet 2 comprises a stationary core member 5 and a winding 6. The armature 3 is provided with slots 7 in which is disposed a. winding 8 that is inductively related to the winding 6 of the electromag- Specication of Letters Patent.

Patented Aug. 31, 1920. 191s. serial No. 240,286.

net 2. The device 4, as illustrated in Fig. 1 of the drawings, comprises a parallel resonant circuit 9 having condensers 10 and 11. and a reactor 12 of such characteristics that parallel resonance will obtain at cycles and no current will traverse the winding 8. Thus, when the proper current traverses the Winding 6, the armature 3 will be attracted toward. the core member 5.y However, the armature 3 will be moved downwardly when the frequency of the current traversing the winding 6 is such that the condenser 11 and the reactor 12 are series resonant. This coii dition may obtain when the frequency is 25 cycles and thus cause the `impedance of the circuit to be zero. Under this condition, such current will traverse the winding 8 as to permit of sufficient repulsion between the windin s 8 and G to overcome the magnetic attraction of the winding 6 with respect to .the armature 3.

It will, of course, be understood` that atv2, to obtain resonance at the frequency at which it is desired to obtain attraction of the armature 3. That is, at 25 cycles, the reactance of the condenser 11 may predominate over the reactance o'f the reactor 12 and the reactance of the two may be such as to obtain vparallel resonance with the` reactor 17. Thus, the im dance of the circuit of the winding 8 wi l be infinity and no current will traverse the same, and t e armature 3 will be attracted. However, on 60 cycles, if the condenser 11 and the reactor 12 are of such characteristics as to be inseries resonance, the impedance of the circuit will be zero and the armature will be repelled.

In Fig. 3 of the drawings, a series resonant titl lf it is desired to cause thearmature 3 to move upwardly at cycles and downwardly at 25 cycles, thel resonant circuit 13 'shown in Fig. t must be such that, at 60 cycles, parallel resonance is established between the reactor 1d andv the condenser 16 and 'the circuit of the Winding 8 Will be of innite impedance. llnder this condition, no current Will traverse the Winding 8 and the armature 3 will be attracted. Similarly, at 25 cycles, if the condenser 18 is of such reactance that series resonance obtains, the impedance of the circuit of the Winding 8 will be Zero and they armature 3 will be moved downwardly by reason of the repulsion between the windings 6 and 8 to overcome the magnetic attraction of the Winding 6 on the armature 8.

'lhe essential feature of ourinvention is that the circuits 9 and 13, comprising re# actors and condensers are connected to the Winding Sand the circuits 9 and 18, are adapted to be series resonant under one frequency and parallel resonant under yanother to thereby cause the armature to be responsive to the frequency, as Well as to the value of the current.

@ur invention is applicable to overload relays or other similar devices in which different operations are desired under different conditionsof frequency, However, our invention is not limited to the specific devices illustrated, as it may be variously modilied Without departing from the spirit and scope of the invention as set forth in the appended claims.

'We claim as our invention: l

1. it relay comprising an electromagnetic actuating means, an armature therefor, means inductively related to the actuating means for controlling the operation of the armature and a resonant circuit connected to said means.

2. it relay comprising an electromagnetic means, a movable Winding inductively related to the electromagnetic means, and a resonant circuit connected to said movable winding.

3. A relay comprising an electromagnetic actuating means, an armature therefor, electromagnetic means associated with the armature and inductively related to theactuating means, and a resonant circuit connected to said second electromagnetic means.

et. A relay comprising an electromagnetic actuating means, an armature therefor, electromagnetic means associated with the armature and inductively related to the actuating means, and a series resonant circuit connected to said second electromagnetic means.

5. it relay comprising an actuating vvinding, an armature therefor, a Winding associated with the armature and inductively related to the actuating Winding, and means connected in circuit with the second Winding for varying the impedance of the secondary Winding in accordance With the frequency of `the current traversing the actuating Winding.

6. A relay comprising an actuating Winding, ank armature therefor, a winding associated With the armture and inductivelyv related to the actuating Winding, and means connected in circuit with the second Winding for so controlling the induced current therein that the armature is attracted under predetermined conditions of frequency of the current traversing the actuating Winding and is repulsed under other predetermined conditions of frequency.

7. di relay comprising an actuating winding, an armature therefor, a Winding associated with the armature and inductively related to the actuating winding, and reactors and condensers connected in circuit with the second Winding to constitute a resonant circuit for so controlling the induced current therein that the armature is attracted by the actuating Winding under predetermined conditions and repelled under other predetermined conditions. c

itt relay comprising an actuating Winding, an armature therefor, a Winding associated with the armature and inductiveiy related to the actuating Winding, and reactors and condensers connected in circuit With the second Winding to constitute a resonant circuit for so controlling the'induced current therein that the armature is attracted by the'actuating Winding under predetermined conditions of the frequency of the current traversing the actuating Winding only. 9. A relay comprising an actuating Winding, a magnetizable armature therefor, a Winding disposed on the armature and inductively related to the actuating Winding, and means for effecting a condition of resonance in the circuit of the second Winding under predetermined conditions. v

10. A relay comprising an actuating Winding, a magnetizable armature therefor, a winding disposed on the armature and inductively related to the actuating Winding. and means for so controlling the impedance of the second-winding circuit that the armature is attracted only when a predetermined o1" a jyredeemned f requency trav- @xses h@ acumng L lezy complisng an eecromagaclfuabnfg means7 n actua'ed member, zssscate gherewth and nule electromagnetic means, and a cu Conuced i@ the Winding.

tesfimony whereof We have heleuno subscmbed oml names Mus 29@ day of May,

BAK/@D Q EAV CHARLES LE G. ORTESCUE, 

